Problem: Simplify the following expression: ${2(-3+3a)-2(a-2)}$
Explanation: Distribute the ${2}$ into the first set of parentheses: $ {2(}\gray{-3+3a}{)} - 2(a-2) $ $ {-6+6a} - 2(a-2) $ Distribute the ${-2}$ into the parentheses: $ -6+6a {-2(}\gray{a-2}{)} $ $ -6+6a {-2a+4} $ Rewrite the expression to group the ${a}$ terms and numeric terms: $ {6a - 2a} {-6 + 4}$ Combine the ${a}$ terms: $ {4a} {-6 + 4}$ Combine the numeric terms: $ {4a} {-2}$ The simplified expression is $4a-2$